TABLE OF CONTENTS. 



CHAPTER II 



THE NATURAL FAMILIES OF THE CTENOPHOR^. 



Section 1. Family diaracters in general among Cteno- 

 pJiorw. — As in all classes of the animal kingdom, the 

 natm'al families of the Aealephs, and those of the Cte- 

 nophorjE in particular, are characterized by particular 

 patterns of form, determined by structural features 

 bearing upon form. p. 187-190. 



Section 2. The natural families of the Ctcnophora 

 Eurystoma:. — Three families may be distinguished in 

 this sub-order: the Beroidic proper, the Neseidoe, and 

 the Rangiidse. p. 190-193. 



Section 3. The natural families of the Ctenophorw Sacca- 

 ta: — This sub-order embraces also three natural families : 

 the ISIertensidae, the Cydippida?, and the Callianirida?, 

 p. 193-198; wliile the Cestida?, p. 198, constitute a 

 sub-order by themselves, p. 292. 



Section 4. The natural families of the Ctenophone Lo- 

 hatcc. — Five families may now bo distinguished in this 

 sub-order: the Euramphreida?, the Bolinida;, the Mne- 

 miida;, the Calynmiida;, and the Oc\Toida;. p. 199-202. 



CHAPTER III. 



NORTH AMERICAN CTENOPHORvE. 



Section 1. The genus Pleurobrachia and its species. — 

 Natural limits of the genus. Its form and structure ; 

 the bulk of the body consists of gigantic cells; their 

 arrangement; the locomotive flappers; the circulation 

 of fluids ; the tentacular apparatus ; the lasso-cells of 

 the tentacles illustrated by Prof H. J. Clark; other 

 structural details, p. 203-248. 



Section 2. The genus Bolina and its speeies ; with remarks 

 on allied genera. • — Characters of the genus ; comparison 

 with Pleurobrachia ; the ambulacral tubes and the loco- 

 motive flappers have not the same extent; the whole 

 chymiferous system and its ramifications diSer in ditfer- 

 ent types of Ctcnophora, p. 249-2G9. Genus IMuemi- 

 opsis, p. 269. 



Section 3. The genus Idyia and other true Beroids. — 

 Difference between Beroe and Idyia as genera. The 

 species belonging to each. Description of the species 

 most common along our coast. Its structure, p. 270. 

 Idyopsis, p. 288. 



Section 4. Tabular view of the Ctenophom known at 

 present. — Systematic enumeration of all the Ctenopho- 

 ra; thus far described, with their principal synonymcs, 

 p. 289-296. 



Section 5. Geographical distribution of the Ctcnopjhora. 

 — First attempt to define the fauns of the sea by 

 the Ctenophoras found in different parts of the world; 

 distinction between faunae and zoological zones, p. 

 297-301. 



